EMARS

Multiscale Seismic Anisotropy in the Earth’s Mantle

Coupling large-scale geodynamic simulations with microstructural rock deformation to understand mantle flow and its seismic signature.

EMARS is a research project under the Consolidación Investigadora Grant CNS2022-135819 funded by MCIN/AEI/10.13039/50110001103 and European Union NextGenerationEU/PRTR) and led by María Gema Llorens (GEO3BCN-CSIC). The project develops a pioneering multiscale framework that links mantle rock deformation at the grain scale with large-scale subduction dynamics to predict seismic anisotropy in the Earth’s mantle

The Scientific Challenge

One of the central questions in modern geodynamics is: How does mantle flow generate the seismic anisotropy observed at the Earth’s surface?

While seismic observations reveal strong anisotropic patterns, connecting these signals to deformation mechanisms and microstructural evolution in mantle rocks remains challenging. Traditional models either focus on grain-scale physics or large-scale plate dynamics, rarely both.

EMARS bridges this gap by directly coupling:

• Microstructural simulations of olivine deformation and dynamic recrystallization

• Large-scale geodynamic models of subduction

• Quantitative predictions of seismic wave propagation
  
  

Project Objectives

1. Simulate Mantle Rock Microstructure Evolution

Numerically reproduce the viscoplastic deformation and dynamic recrystallization of olivine aggregates using full-field models (VPFFT-ELLE and ReX-VPSC).
Status: 100% completed

2. Predict Seismic Anisotropy

Compute seismic velocities (Vp, Vs) and anisotropy from simulated crystallographic preferred orientations (CPO), linking deformation directly to observable seismic signals.
Status: 100% completed

3. Establish General Laws Relating Mantle Flow and Seismic Observations

Derive empirical and functional relationships connecting mantle physical parameters (temperature, pressure, deformation history) to seismic anisotropy.
Status: Ongoing (advanced stage)

Methodological Innovation

EMARS introduces a multiscale computational strategy that integrates:

Microstructural Modeling

• Full-field viscoplastic simulations (VPFFT coupled to ELLE)
  
  

• Dynamic recrystallization mechanisms (grain boundary migration, subgrain rotation, recovery)
  
  

• Olivine slip system calibration adapted from metallurgical frameworks
  
  

Seismic Property Computation

• Texture and elastic property analysis using MTEX
  
  

• Calculation of anisotropic Vp and Vs
  
  

• Evaluation of both seismic and mechanical anisotropy
  
  

Large-Scale Geodynamics

• Subduction modeling with UWGeodynamics
  
  

• Extraction of deformation tensors along particle trajectories
  
  

• Coupling of macro-scale strain histories with grain-scale simulations
  
  

Scientific Output

EMARS has produced peer-reviewed publications in high-impact journals including:

1.- Yu, Y., Griera, A., Gomez-Rivas, E., Bons, P. D., Garcia-Castellanos, D., Hao, B., & Llorens, M. G. (2025).

Microstructure and CPO evolution of dynamically recrystallized olivine during complex deformation conditions: a full-field numerical modeling approach.

Journal of Structural Geology, 105500.

2. Yu, Y., Griera, A., Gomez-Rivas, E., Bons, P. D., García-Castellanos, D., Hao, B., & Llorens, M. G. (2024).

Dynamic recrystallization of olivine during simple shear: Evolution of microstructure and crystallographic preferred orientation from full-field numerical simulations.

Geochemistry, Geophysics, Geosystems, 25(9), e2023GC011212.

3. Hao, B., Griera, A., Llorens, M. G., Bons, P. D., Lebensohn, R. A., Yu, Y., & Gomez-Rivas, E. (2025).

The influence of kinematics of deformation on polycrystalline halite dynamic recrystallization: Full-field simulation of simple shear versus pure shear.

Journal of Structural Geology, 197, 105424.

4. Hao, B., Llorens, M. G., Griera, A., Bons, P. D., Lebensohn, R. A., Yu, Y., & Gomez-Rivas, E. (2023).

Full-field numerical simulation of halite dynamic recrystallization from subgrain rotation to grain boundary migration.

Journal of Geophysical Research: Solid Earth, 128(12), e2023JB027590.

EGU 2025 (Vienna)

Oral presentation

Authors: Maria-Gema Llorens, Eloi González-Esvertit, Albert Griera, Chao Qi, Claudia Prieto-Torrell, Enrique Gómez-Rivas, Yuanchao Yu, Ricardo Lebensohn.

EGU 2024 (Vienna)

Poster presentation

Authors: Yuanchao Yu, Maria-Gema Llorens, Albert Griera, Enrique Gomez-Rivas, Paul D. Bons, Daniel Garcia-Castellanos, Baoqin Hao, Ricardo A. Lebensohn.

Oral presentation

Authors: Hao, B., Llorens, M.-G., Griera, A., Bons, P. D., Lebensohn, R. A., Yu, Y., Gomez-Rivas, E.

DRT 2024 (Barcelona)

Poster presentation

Authors: Llorens, M.-G., Griera, A., Bons, P. D., Weikusat, I., Prior, D., Gomez-Rivas, E., de Riese, T., Jimenez-Munt, I., García-Castellanos, D., Lebensohn, R. A.

Societal Relevance

Although fundamental in nature, improved interpretation of seismic anisotropy enhances:

• Understanding of tectonic processes
  
  

• Geohazard assessment in subduction zones
  
  

• Geophysical interpretation frameworks
  
  

Team and Collaborations

Principal Investigator
María Gema Llorens — GEO3BCN-CSIC

Technical Research Staff

• Josep Andreu Sabaté (3D geodynamic modeling, HPC)
  
  

• Eloi González-Esvertit (full-field microstructural modeling)
  
  

International Collaborations

• Los Alamos National Laboratory (VPFFT development)

• MIT (seismic anisotropy expertise)

• Universität Tübingen (ELLE platform)
  
  

Funding

EMARS is funded by the Spanish State Research Agency under the Consolidación Investigadora 2022 program (CNS2022-135819), Ministry of Science, Innovation and Universities, Government of Spain

Project duration: September 2023 – August 2025
Host Institution: GEO3BCN – CSIC

Contact

María Gema Llorens
GEO3BCN – Geosciences Barcelona (CSIC)
Barcelona, Spain